1
Features
?Transformerless 2W to 4W conversion ?Controls battery feed to line ?Programmable line impedance
?Programmable network balance impedance ?Off-hook and dial pulse detection ?Ring ground over-current protection ?Programmable gain
?Programmable constant current feed ?
-22V to -72V battery operation
Applications
Line interface for:?PABX/ONS ?Intercoms ?Key Telephone Systems
?
Control Systems Description
The Zarlink MT91600 provides an interface between a switching system and a subscriber loop, mainly for short loop SLIC applications. The functions provided by the MT91600 include battery feed, programmable constant current, 2W to 4W conversion, off-hook and dial pulse detection, user definable line and network balance impedance’s and the capability of programming the audio gain externally. The device is fabricated as a CMOS circuit in a 28 pin SSOP package.
February 2005
Ordering Information
MT91600AN 28 Pin SSOP Tubes
MT91600ANR 28 Pin SSOP Tape & Reel MT91600AN128 Pin SSOP*Tubes
MT91600ANR128 Pin SSOP*
Tape & Reel
*Pb Free Matte Tin
-40°C to +85°C
MT91600
Programmable SLIC
Data Sheet
Figure 1 - Functional Block Diagram
TD
RING Tip Drive Controller
Audio Gain & Network
Balance Circuit
2 W to 4 W Conversion & Line Impedance
Relay Driver
Line Sense
Over-Current Protection Circuit
Ring Drive Controller
Loop Supervision
TIP TF RF C3A C3B RV RD
VR
Z3Z2Z1RLYC RLYD
VEE
GND VDD C2B C2A C1SHK VREF IC X3
X2
X1
VX https://https://www.doczj.com/doc/c411912356.html,
MT91600
Data Sheet
Change Summary
Figure 2 - Pin Connections
Page Item
Change
10
Figure 5
Updated Application Diagram
Pin Description Pin #Name Description
1VDD Positive supply rail, +5V.
2TD Tip Drive (Output). Controls the Tip transistor.
3TF Tip Feed. Connects to the Tip transistor and to the TIP lead via the Tip feed resistor. 4TIP Tip. Connects to the TIP lead of the telephone line. 5RING Ring. Connects to the RING lead of the telephone line.
6
VREF
Reference Voltage (Input). This pin is used to set the subscribers loop constant current. Changing the input voltage sets the current to any desired value within the working limits. VREF is related to VLC.
7IC Internal Connection (Input). This pin must be connected to GND for normal operation.8RF Ring Feed. Connects to the RING lead via the Ring feed resistor.
9RV Ring Voltage and Audio Feed. Connects directly to the Ring drive transistor and also to Ring Feed via a relay.
10RD Ring Drive (Output). Controls the Ring transistor.
11C3A A filter capacitor for over-current protection is connected between this pin and GND.12C3B A filter capacitor for over-current protection is connected between this pin and GND.13C2B A capacitor for loop current stability is connected between this pin and C2A.14C2A A capacitor for loop current stability is connected between this pin and C2B.
15
Z1
Line Impedance Node 1. A resistor of scaled value "k" is connected between Z1 and Z2. This connection can not be left open circuit.
Z3X3VREF RLYD VEE RF GND Z2IC RING TIP RV 12345678910111213142827262524232221201918171615
TF VDD TD RD C3A C3B C2B C2A RLYC SHK C1X2VR VX X1Z1
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MT91600
Data Sheet
Functional Description
The MT91600 is the analog SLIC for use in a 4 Wire switched system. The SLIC performs all of the normal interface functions between the CODEC or switching system and the analog telephone line such as 2W to 4W conversion,constant current feed, ringing and ring trip detection, current limiting, switch hook indication and line and network balance impedance setting using minimal external components.Refer to Figure 5 for MT91600 components designation.
2 Wire to 4 Wire Conversion
The hybrid performs 2 wire to 4 wire conversion by taking the 4 wire signal from an analog switch or voice CODEC,a.c. coupled to VRIN, and converting it to a 2 wire differential signal at tip and ring. The 2 wire signal applied to tip and ring by the telephone is converted to a 4 wire signal and should be a.c. coupled to Vx which is the output from the SLIC to the analog switch or voice CODEC input.
Gain Control
It is possible to set the Transmit and Receive gains by the selection of the appropriate external components.The gains can be calculated by the formulae:2W to 4W gain:
Gain 2 - 4 = 20*Log [ R13 / R12]4W to 2W gain:
Gain 4 - 2 = 20*Log [0.891 * (R14 / R15)]
16Z2Line Impedance Node 2. This is the common connection node between Z1 and Z3.17Z3Line Impedance Node 3. A network either resistive or complex of scaled value "k" is connected between Z3 and Z2. This connection can not be left open circuit.18X1Gain Node 1. This is the common node between Z3 and VX where resistors are connected to set the 2W to 4W gain.
19VX Transmit Audio (Output). This is the 4W analog signal to the SLIC.
20X3Gain Node 3. This is the common node between VR and the audio input from the CODEC or switching network where resistors are fitted to sets the 4W to 2W gain 21VR Receive Audio (Input). This is the 4W analog signal to the SLIC.
22X2Gain Node 2. Networks, either resistive or complex, are connected between this node, VR and GND to set the Network Balance Impedance for the SLIC.23C1 A filter capacitor for ring trip is connected between this pin and GND.
24SHK Switch Hook (Output). This pin indicates the line state of the subscribers telephone. The output can also be used for dial pulse monitoring. SHK is high in off-hook state.25RLYC Relay Control (Input). An active high on this pin will switch RLYD low.
26RLYD Inverted Output of RLYC. It is used to drive the bipolar transistor that drives the relay (see Figure 5.)
27GND Ground. Return path for +5V and -5V. This should also be connected back to the return path for the loop battery, LGND and relay drive ground RLYGND.28
VEE
Negative supply rail, -5V.
Pin Description (continued)Pin #Name Description
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MT91600Data Sheet
Impedance Programming
The MT91600 allows the designer to set the device’s impedance across TIP and RING, (Z TR), and network balance impedance, (Z NB), separately with external low cost components.
For a resistive load, the impedance (Z TR) is set by R11 and R18. For a complex load, the impedance (Z TR) is set by R11, R18, R19 & C8 (see Figure 5.)
The network balance, (Z NB), is set by R16, R17 & C3 (see Figure 5.)
The network balance impedance should be calculated once the 2W - 4W gain has been set.
Line Impedance
For optimum performance, the characteristic impedance of the line, (Z o), and the device’s impedance across TIP and RING, (Z TR), should match. Therefore:
Z o = Z TR
The relationship between Z o and the components that set Z TR is given by the formula:
Z o / ( R1+R2) = kZ o / R11
where kZ o = Z LZ
Z LZ = R18, for a resistive load.
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Z LZ = [R18 + (R19 // C8)], for a complex load.
The value of k can be set by the designer to be any value between 20 and 250. Three rules to ensure the correct operation of the circuit:
(A) R18 + R19 > 50k?
(B) R1 = R2.
(C) R11 > =50k?
It is advisable to place these components as close as possible to the SLIC.
Network Balance Impedance
The network balance impedance, (Z NB), will set the transhybrid loss performance for the circuit. The balance of the circuit is independent of the 4 - 2 Wire gain but is a function of the 2 - 4 Wire gain.
The method of setting the values for R16 and R17 is given by the formula:
R17 = [1.782 * Z o / ( Z o+Z NB) * ( R13 / R12 )]
R17 + R16[1 + R13 / R12]
where Z NB is the network balance impedance of the SLIC and Z o is the line impedance.
(R16 + R17) >= 50k?
It is advisable to place these components as close as possible to the SLIC.
MT91600Data Sheet
Loop Supervision & Dial Pulse Detection
The Loop Supervision circuit monitors the state of the phone line and when the phone goes "Off Hook" the SHK pin goes high to indicate this state. This pin reverts to a low state when the phone goes back "On Hook" or if the loop resistance is too high for the circuit to continue to support a constant current.
The SHK output can also be monitored for dialing information when used in a dial pulse system.
Constant Current Control
The SLIC employs a feedback circuit to supply a constant feed current to the line. This is done by sensing the sum of the voltages across the feed resistors, R1 and R2, and comparing it to the input reference voltage, Vref, that determines the constant current feed current.
The MT91600’s programmable current range is between 18mA to 32mA.
Line Drivers & Overcurrent Protection
The Line Drivers control the external Battery Feed circuit which provide power to the line and allows bi-directional audio transmission.
The loop supervision circuitry provides bias to the line drivers to feed a constant current while the over-current protection circuitry prevents the ring driver from causing the ring transistor to overload.
The line impedance presented by the Line Driver circuitry is determined by the external network, which may be purely resistive or complex, allowing the circuit to be configured for use in any application. The impedance can also https://https://www.doczj.com/doc/c411912356.html,
be fixed to one value and modified to look like a different value by reflecting an impedance through the SLIC from an intelligent CODEC or DSP module.
There is long term protection on the RING output against accidental short circuits that may be applied either across TIP/RING to GND or RING to GND. This high current will be sensed and limited to a value that will protect the circuit.
In situations where an accidental short circuit occurs either across TIP/RING to GND or RING to GND, an excessive amount of current will flow through the ring drive transistor, Q3. Although the MT91600 will sense this high current and limit it, if the power rating of Q3 is not high enough, it may suffer permanent damage. In this case, a power sharing resistor, R23, can be inserted (see Figure 5) to dissipate some of the power. Capacitor C13 is inserted to provide an a.c. ground point. The criteria for selecting a value for the power sharing resistor R23 can be found in the application section of this data sheet.
Ringing and Ring Trip Detection
Ringing is applied to the line by disconnecting pin 8, RF, from pin 9, RV, and connecting it to a ringing source which is battery backed. This may be done by use of an electro-mechanical relay. The SLIC is capable of detecting an Off Hook condition during ringing by filtering out the large A.C. component by use of the external components connected to pin 23. This filter allows an Off Hook condition to be monitored at SHK, pin 24.
When using DTMF signalling only i.e., pulse dialling is not used, the capacitor, C7, can be permanently connected to ground and does not require to be switched out during dialling.
Power up Sequence
The circuit should be powered up in the following order: AGND, VEE, VDD, V BAT.
MT91600
Data Sheet
Application
The following Application section is intended to demonstrate to the user the methods used in calculating and selecting the external programming components in implementing the MT91600 as an analog line interface in a communication system. The programming component values calculated below results in the optimum performance of the device.
Refer to Figure 5 for MT91600 components designation.
Component Selection
Feed Resistors (R1, R2)
The selection of feed resistors, R1 and R2, can significantly affect the performance of the MT91600. It is recommended that their values fall in the range of:
200? <= R1 <= 250?
where, R1 = R2
The resistors should have a tolerance of 1% (0.15% matched) and a power rating of 1 Watt.Loop Current Setting (R3, R4, C9)
By using a resistive divider network, (Figure 3), it is possible to maintain the required voltage at Vref to set I LOOP .The loop current programming is based on the following relationship:
I LOOP = - [ F * V LC + G * V BAT ] * K o * H (R1 +R2)
where, F = R4 / (R4 + R3)
G = R3 / (R4 +R3)
K o = 200000 / (200000 + (R4//R3) )H = 1.07
I LOOP is in Ampere From Figure 3 with R1 = R2 = 220? For I LOOP = 25mA, V LC = 0V, Vbat=-48V
Figure 3 - Resistor Divider
R343k ?
V LC
V REF
6MT91600
R4130k ?
V BAT
C9 100nF
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MT91600
Data Sheet
C9 is inserted to ensure pin 6, Vref, remains at a.c. ground. 100nF is recommended.
I LOOP can also be set by directly driving Vref with a low impedance voltage source. (See Figure 4). It is recommended that a small resistor be placed in series with the Vref pin. In this case:I LOOP = 1.07 * Vs
where, Vs < 0
(R1 +R2)
Figure 4 - Direct Voltage
Calculating Component Values For AC Transmission
There are five parameters a designer should know before starting the component calculations. These five parameters are:
1) characteristic impedance of the line Z o 2) network balance impedance Z NB
3) value of the feed resistors (R1 and R2)4) 2W to 4W transmit gain 5) 4W to 2W receive gain
The following example will outline a step by step procedure for calculating component values. Given:
Z o = 600?, Z NB = 600?, R1=R2= 220?Gain 2 - 4 = -1dB, Gain 4 - 2 = -1dB
Step 1: Gain Setting (R12, R13, R14, R15)Gain 2 - 4 = 20 Log [ R13 / R12] -1 dB = 20 Log [R13 / R12] ∴ R12 = 112.2k ?, R13 = 100k ?.Gain 4 - 2 = 20 Log [0.891 * [R14 / R15)] -1 dB = 20 Log [0.891 * [R14 / R15)] ∴ R14 = 100k ?, R15 = 100k ?.
2k ?
V REF
6
MT91600
C9 100nF
Vs
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MT91600Data Sheet
Step 2: Impedance Matching (R11, R18, R19, C8)
a) Z o / ( R1+R2) = kZ o / R11
600/(220+220) = (k*600)/R11
let k = 125
∴ R11 = 55k?.
b) In general,
kZ o = Z LZ
where:
Z LZ = R18, for a resistive load.
Z LZ = [R18 + (R19 // C8)], for a complex load.
Since we are dealing with a resistive load in this example Z LZ = R18, and therefore:
kZ o = R18
(125 * 600)= R18
∴ R18 = 75k?.
Step 3: Network Balance Impedance (R16, R17)
R17 = [1.782 * Z o / ( Z o+Z NB) * ( R13 / R12 )]
R17 + R16[1 + R13 / R12)]
R17 = 0.4199
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R17 + R16
set R17 = 100k?, R16 becomes 138k?.
∴ R16 = 138k?, R17 = 100k?.
Complex Line Impedance, Z o
In situations where the characteristic impedance of the line Z o is a complex value, determining the component values for impedance matching (R11, R18, R19, C8) is as follows:
Given Z o = 220? + (820? // 120nF)
Z o / ( R1+R2) = kZ o / R11 (Equation 1)
where, kZ o = [R18 + (R19 // C8)]
Choose a standard value for C8 to find a suitable value for k.
Since 1nF exists, let C8 = 1nF then,
k = 120nF / C8
k = 120nF / 1nF
∴k =120
R18 = k * 220?
R18 = 120 * 220?
R18 = 26400
R19 = k * 820?
R19 = 120 * 820
R19 = 98400
∴ R18 = 26k4?, R19 = 98k4?
MT91600Data Sheet
From (Equation 1)
R11 = k * (R1 + R2)
R11 = 120 * (220? + 220?)
∴ R11 = 52k8?
Power Sharing Resistor (R23)
To determine the value of R23, use the following equations:
R23(max)= |Vbat(min)| - 100 - (2*R2 + Lr + DCRP)
30mA
R23(min)= |Vbat(max)| - Pd(max) - R2
40mA 1.6mA
where,
Vbat(min/max) = the expected variation of Vbat.
R2 = the feed resistor.
Lr = maximum DC loop resistance.
DCRP = DC resistance of the phone set.
Pd(max) = the maximum power dissipation of the ring drive transistor Q3.
If R23(max) > R23(min), then set R23 to be the geometric center:
R23 = Square Root (R23(max) * R23(min))
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If R23(max) < R23(min), then a violation has occurred. Pd(max) will have to be increased.
If R23 = negative value, power sharing is not required, i.e., R23=0
A numerical example:
Given:
R2 = 220?
Lr = 325? (2.5km of 28 gauge wire, averaged at 65?/km)
DCRP = 200?
Pd(max) = 1.5W
Vbat = -48V +/- 10% (i.e. -43V to -53V)
Therefore:
R23(max) = (43/30mA) - 100 - (2 * 220 + 325 + 200)
= 1433.3 - 100 - 965
R23(max) = 368.3?
R23(min) = (53/40mA) - (1.5/1.6mA) - 220
= 1325 - 937.5 - 220
R23(min) = 167.5 ?
R23 = Square Root ( 368.3 * 167.5 )
R23 = 248.4?
MT91600
Data Sheet
Figure 5 - Typical Application
MT91600
SHK RLYC VRLY
Q4
C4
242526
VEE VDD
V LC
R3
K1
D1
7
27
28
1
6
R4V BAT
C9
2
3
Q1
D2a
R1
D2b
4
R21
TIP
R20
RING
5
R2
8
~
V BAT
D3a
D3b
9
R9
R 7
VDD
C5
R6
R 5
90 Vrms
Q3
V BAT=-48V
R 8
10
Q2
15
16
14
1312
11C10
C2
C1
17
18
19
C8
R 18 R 13
VX
R15
VRIN
2021
R 14
R16R17
K1b
22
C3
C7
C6
23
PR1
K1a
C11
R 19
R22
R10
C12
V BAT V BAT
R 11R 12
Z LZ
R 18
Impedance Z LZ
Resistive Load Z o
Complex Load Z o
VDD TD
TF
TIP
RING
VREF
RF
RV RLYC
SHK RLYD
VEE
GND
IC
C1
X2
VR X3VX
X1
Z3
Z2
Z1
RD
C3A
C3B
C2B
C2A
R 23
C13
D4
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MT91600
Data Sheet
Note: All resistors are 1/4W, 1% unless otherwise indicated.
*Assumes Z o = Z NB = 600?, Gain 2 - 4 = -1dB, Gain 4 - 2 = -1dB.
Decoupling capacitors, (1uF, 100V, 20%), can be added to V DD , V EE , V BAT and V RLY to provide improved PSRR performance.
K1=Electro-mechanical relay, 5V, DPDT/2 FORM C
PR1=This device must always be fitted to ensure damage does not occur from inductive loads.For simple applications, PR1 can be replaced by a single TVS, such as 1.5KE220C, across tip and ring. For applications requiring lightning and mains cross protection further circuitry will be required and the following protection devices are suggested: P2353AA, P2353AB (Teccor), THBT20011, THBT20012, THBT200S (SGS-Thomson), TISP2290,TSSP8290L (T.I.)
Component List* for a Typical Application with a Resistive 600? Line Impendance - Refer to Figure 5 for
component designation and recommended configuration
Resistor Values
R1220? 1% (0.15% matched), 1W
R2220? 1% (0.15% matched), 1W
R343k ?R4130k ?R5220?R675k ?R73k ?R81k ?R91k ?R10560k ?R1155k ?R12112k ?R13100k ?R14100k ?R15100k ?R16138k ?R17100k ?R1875k ?R190?R202k ?R212k ?R22
1k ?
R23
248?
Capacitor Values
C1100nF, 5%
C2
300nF, 5%C3100pF, 5%C4
33nF, 20%
C5 3.3nF, 5%C61uF, 20%, 16V
C7100nF, 20%C80F C9100nF, 20%C10100nF, 5%C1147pF, 20%C12
33nF, 10%
C13
100nF 20%
Diodes and Transistors
D1BAS16 or equivalent D2a/b BAV99 dual diode or equivalent D3a/b BAV99 dual diode or equivalent Q12N2222 or MPSA42 or MMBTA42Q22N2907 or MPSA92 or MMBTA92Q32N2222 or MPSA42 or MMBTA42Q4
2N2907 or MPSA92 or MMBTA92
D4
1N5242 12V Zener or equivalent
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MT91600
Data Sheet
*Exceeding these values may cause permanent damage. Functional operation under these conditions is not implied.
Note 1: Voltage at Vref pin set by VLC and potential divider.
Note 2: Tip and Ring must not be shorted together and to ground at the same time.
Note 3: The device contains circuitry to protect the inputs from static voltage up to 500V. However, precautions should be taken to avoid static charge build up when handling the device.
? Typical figures are at 25°C with nominal supply voltages and are for design aid only
?Electrical Characteristics are over Recommended Operating Conditions unless otherwise stated.?Typical figures are at 25°C with nominal + 5V supplies and are for design aid only.
Note 4: 16 to 68Hz superimposed on a V BAT .
Absolute Maximum Ratings*
Parameter
Sym.Min.Max.Units Comments
1
DC Supply Voltages
V DD V EE V BAT -0.3-6.5-80
+6.5+0.3+0.3V V V Limited by the Drive transistor, Q3.2Ringing Voltages
Vring 100Vrms Superimposed on V BAT
3Voltage setting for Loop Current V REF
-20+0.3V Note 1
4Overvoltage Tip/GND Ring/GND, Tip/Ring 200
V MAX 1ms (with power on)
5Ringing Current
Iring
30mA. RMS 6Ring Ground over-current 45
mA Note 2
7Storage Temp
Tstg -65
+150°C 8Package Power Dissipation Pdiss
0.10W +85°C max, V BAT = -48V 9
ESD Rating
500
V
Human Body Model
Note 3
Recommended Operating Conditions
Parameter
Sym.Min.Typ.?Max.Units Test Conditions
1
Operating
Supply Voltages V DD V EE V BAT 4.75-5.25-72 5.00-5.00-48 5.25-4.75-22
V V V 2Ringing Voltage
Vring 0
50V RMS Note 4
3
Voltage setting for Loop Current
VREF
-10.3
V
I LOOP = 25mA, R1=R2=220?V BAT = -48V
4Operating Temperature To -40+25+85°C
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MT91600
Data Sheet
?Electrical Characteristics are over Recommended Operating Conditions unless otherwise stated.?
Typical figures are at 25°C with nominal +5V and are for design aid only.Note 5: Off hook detection is related to loop current.
DC Electrical Characteristics ?
Characteristics
Sym.Min.
Typ.?
Max.Units Test Conditions
1
Supply Current
I DD I EE I BAT 25118.545mA mA mA 2Power Consumption PC 6090mW Standby/Active 3
Constant Current Line Feed
I LOOP
2225
28
mA
V REF = -10.3V
Test circuit as Fig. 6V BAT = -48V
4Programmable Loop Current Range I LOOP 1832mA 5
Operating Loop
(inclusive of Telephone Set)
R LOOP
1200450
??
I LOOP = 18mA V BAT = -48V I LOOP = 18mA V BAT = -22V
6Off Hook Detection Threshold SHK 20mA
V REF = -10.3V V BAT = -48V
See Note 5. I LOOP = 25mA 7
RLYC
Input Low Voltage Input High Voltage Vil Vih
2.0
0.40.7
V V
lil = 50μA lih = +50μA 8
SHK
Output Low Voltage Output High Voltage Vol Voh
2.7
0.4
V V Lol = 8mA Loh = -0.4mA
8
Dial Pulse Distortion ON OFF
+4+4
ms ms
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MT91600
Data Sheet
?
Electrical Characteristics are over Recommended Operating Conditions unless otherwise stated.?Typical figures are at 25°C with nominal +5V and are for design aid only.
Note 6: Assumes Z o = Z NB = 600? and both transmit and receive gains are programmed externally to -1dB, i.e. Gain 2-4 = -1dB, Gain 4-2 = -1dB .
AC Electrical Characteristics ?
Characteristics
Sym.Min.
Typ.?Max.Units Test Conditions
1Ring Trip Detect Time Tt
100300
mS 2Output Impedance at VX 10?3Gain 4-2 @ 1kHz -1.3
-1-0.8dB Note 6
Test circuit as Fig. 84Gain Relative to 1kHz ±0.15dB 300Hz - 3400Hz 5
Transhybrid Loss
THL
2025
dB
Note 6
300Hz - 3400Hz Test circuit as Fig. 86Gain 2-4 @ 1kHz -1.3-1-0.8dB Note 6
Test circuit as Fig. 77Gain Relative to 1kHz ±0.15
dB
300Hz to 3400Hz 8
Return Loss at 2-Wire
RL
2030dB
Note 6
300Hz - 3400Hz Test circuit as Fig. 109
Total Harmonic Distortion
@2W @VX THD
0.30.3
1.01.0
%%
3dBm,1kHz @2W 1Vrms, 1KHz @ 4W 10Common Mode Rejection 2 wire to Vx
CMR 3542dB
Input 0.5Vrms, 1KHz Test circuit as Fig. 911Longitudinal to Metallic Balance LCL
55dB 200Hz to 3400Hz Test circuit as Fig. 912Metallic to Longitudinal Balance 58
48
dB dB
200Hz to 1000Hz 1000Hz to 3400Hz 13
Idle Channel Noise
@2W @VX Nc
1212
dBrnC dBrnC
Cmessage Filter Cmessage Filter
14Power Supply Rejection Ratio at 2W and VX
Vdd Vee
PSRR
2323
dB dB
0.1Vp-p @ 1kHz
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MT91600
Data Sheet
Test Circuits
Figures 6, 7, 8, 9 and 10 are for illustrating the principles involved in making measurements and do not necessarily reflect the actual method used in production testing.
Figure 6 - Loop current programming
Figure 7 - 2-4 Wire Gain
Figure 8 - 4-2 Wire Gain & Transhybrid Loss
SLIC
6
I Loop
TIP RING
Z o
V LC
R3R 4
V BAT
C9
SLIC
19
TIP
RING
Z o 2
__Z o 2
__~
V TR
V S
V X
Gain = 20*Log(V X /V TR )
R 1217
18
R 13
20
R15
SLIC
20TIP
RING
Z o
~V TR
V
S
Gain = 20*Log(V TR /V S )R15R 14
R16
R17
C3
C1121
22V X
19
THL = 20*Log(V X /V S )
VRIN
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MT91600
Data Sheet
Figure 9 - Longitudinal Balance & CMR
Figure 10 - Return Loss
SLIC
Long. Bal. = 20*Log(V TR /V S )V X
19
CMR = 20*Log(V X /V S )
TIP RING
Z o 2
__Z o 2
__~
V TR
V S
R15
20
SLIC
TIP
RING
R
~
V S
Gain = 20*Log(2*V Z /V S )
20
R15
Z o
R
V Z
C8
R 18
R 19
R 11
17
16
15
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